Method of dyeing only the cellulose acetate ends of a mixed fabric using a dye paste comprising a swelling agent for the cellulose acetate



1951 B. J. GOLDSMITH ETAL 2,57

METHOD OF DYEING ONLY THE CELLULOSE ACETATE ENDS OF A MIXED FABRIC USING A DYE PASTE COMPRISING A SWELLING AGENT FOR THE CELLULOSE ACETATE Filed May 7, 1947 Patented Nov. 6, 1951 METHOD OF DYEING ONLY THE CELLULOSE ACETATE ENDS OF A MIXED FABRIC USING A DYE PASTE COMPRISING A SWELLING AGENT FOR THE CELLULOSE ACETATE Bertram J. Goldsmith, Neshanic, N. J and Walter H. Hindle, Allentown, Pa., assignors to Royal Swan, Inc., Dover, Del.

Application May 7, 1947, Serial No. 746,464

8 Claims. .1

This invention relates to new and useful improvements in methods of dyeing textile fabrics and has particular reference to jacquard fabrics.

An object of the invention is to provide a simple and efficient method whereby the fabrics may be dyed and result in acolored design on a clear white or contrasting background.

The coloration of flat textile fabrics, of which jacquard woven labels are an example, has been hitherto been carried out on conventional lines. Either the labels were woven from warps of which some ends were previously dyed and then filled with white yarn, or else the label fabrics were woven with different types of fibers in the warp and the filling, and the coloration wa accornplished by using dyestuffs capable .of coloring one fiber only, the other fiber being left white.

For example, a label might be made of warps consisting of cellulose acetate and regenerated cellulose and the filling of regenerated cellulose only. As the design or wording on the label is produced by utilizing the cellulose acetate warps,

it follows that, when the label or fiat fabric is dyed with dyestuff having affinity for cellulose acetate and no afiinity for regenerated cellulose, a colored design on a white background may be obtained.

There is one objection which is found in this process or method and that is that the portion of the cellulose acetate warp which appear at the rear of the fabric is also dyed in the same shade as the ends which form the design on the face of the label. Whether the warp ends are dyed before weaving or after weaving as described above, the degree of coloration of the warp at the rear of the flat surface is such'that it is plainly visible through the face of the label and instead of having, for instance, a bluedesign on a white background, the showing through of the dyed rear warp ends gives the effect of a blue design on a blue-gray background, and this militates against the clarity and sharp contrast between the design and the background which is desired at all times.

The invention herein which is designed to achieve the above objects, in brief and very general terms concerns the application, to one surface only of the fiat fabric preferably, of athick viscous liquid containing a dyestuff so that those ends of the fabric which are reactive to the dye-' stuff will be colored and those which are not'will not be affected and furthermore the liquid; because of its viscosity will not run through and dye the rear portions of the responsive ends so that a sharp contrasting background is thereby achieved. 1

. penetration of the fabric from face to back is impossible. This results in the certain ends which appear on the face of the fabric being dyed, and the portions of these same ends which appear at the rear face of the fabric are completely untouched by the dyestuff paste.

Furthermore, after the paste has thus been spread across the face of the fabric, the fabric is dried rapidly and then washed vigorously.

Still further the invention concerns the provision of a paste the composition of which inaffinity for cellulose acetate under the conditions.

cludes a dye solvent, a plasticiser for the ends to be treated, and a thickening agent for the liquid employed, examples of which are given hereinafter.

Further and more specific objects, features, and advantages will more clearly appear from a consideration of the detailed specification hereinafter set forth especially when taken in connection with the diagrammatic representation of the apparatus employed and which forms part of the specification.

The single figure of the drawing illustrates one simple form of the combination of apparatus which may be used t carry out the process 6ffectively.

Referring now to the specific form of the invention which, among other forms, has been effectively demonstrated in practice, it has been discovered that by spreading a dye paste of very heavy viscosity containing dyestuffs which have hereafter mentioned, across the face of, for example, a continuous strip of narrow fabric to be formed into labels, and having warps made from cellulose acetate and regenerated cellulose and filled with regenerated cellulose ends, the viscosity of thedye paste is such that a complete penetration of the material from face to back is impossible. This results in the cellulose acetate warp ends which appear on the face of the fabric being dyed, although the whole face of the fabric, atthis point in the process is colored, and the cellulose acetate warp ends which appear at the rear face of the fabric are completely untouched by the dyestuff paste.

After the dye paste has been spread across the face of the fabric, which may be made in continuous' ribbon form to manufacture colored labels, so that, for instance, there may be 25 labels in each yard'of the ribbon, the ribbon is then dried rapidly and washed vigorously. The washing serves to remove the dyestuif paste from the fibers in the label for which the dyestuff has no affinity and which is only applied mechanically. The cellulose acetate fibers, of course, having an aflinity for the paste, retain the dyestuff to produce a perfectly colored design on a completely white background, since the acetate warp ends at the rear of the label remain perfectly white.

A comparison of the labels colored by conventional means and by the method described above shows that whereas the supposedly white background of the former has a distinctly soiled or colored appearance, the white background obtained by our method is noteworthy for the clarity and sharp contrast of the background.

In more detail the method includes the manufacture of a dye paste by dissolving 16 grams of #400 viscosity methyl cellulose in 3'75 cc. of ethyl alcohol, and 125 cc. of water which contains 25 grams of sodium thiocyanate previously dissolved. The former is introduced as a thickening agent and the latter as a plasticiser for the cellulose acetate ends.

To this paste is added 15 grams of W001 Blue GL, color index 833. This latter is merely indicative of many colors which may be used.

The paste is then allowed to drop on to the face of the fabric in the form of a ribbon, although any other flat surface may thus be treated, and i spread thereon and the excess removed by means of a spreader or blade. The ribbon then passes beneath a series of heater elements, which may be infra-red heating bulbs, which serve to evaporate the ethyl alcohol, which action in turn aids in the fixation of the dyestuff upon the cellulose acetate fiber on the one face only of the fabric.

Although the ethyl alcohol is used in the example given above, as the dye solvent, any of the lower aliphatic alcohols would satisfactorily serve the same purpose. For instance, methyl alcohol, isopropyl alcohol, normal-, secondary-, and. tertiary butyl alcohol, and normal-, secondary-, and tertiary-amyl alcohol may be used.

Whereas sodium thiocyanate is used in the example as a plasticiser for the cellulose acetate fibers, equally good results may be obtained by the use of any plasticiser or swelling agent or solvent for cellulose acetate; for instance, ammonium thiocyanate, zinc thiocyanate, potassium thiocyanate, acetic acid, formic acid and phenol, may be employed.

It is to be noted that the plasticiser may even be omitted if the temperature of the dye paste is raised to 60 degrees C., for at this temperature the ethyl alcohol present acts as a plasticiser for the cellulose acetate.

Although methyl cellulose is used as a thickening agent in the above example, any material which will form heavy viscous solutions in lower aliphatic alcohol-water solutions will serve the same useful purpose. For instance, ethyl cellulose and carboxy methyl cellulose may be used.

In the above example, an acid type of dyestuff is used as a coloring material, but dyestuffs of the dispersed type, normally used for dyeing cellulose acetate and known commercially a the S. R. A. type dyestufis, will yield equally good results.

In the drawing, the simple diagram illustrates the apparatus employed to carry out the novel method and shows that the ribbon-like fabric passes from the roll A through and between tension rollers B, to a device D of any suitable construction in which a blade will spread the paste or liquid on the ribbon, the paste being contained in a storage tank D from which it drops in to the device which spreads it. The

' ribbon is then continuously passed beneath a heating device in the form of a battery of lamps E, preferably of the infra-red type, into a Washing and drying device E, and around a series of rollers, including the guide roller F and then back to the wind-up roll G at which time it is thoroughly dyed and dried.

While the invention has been described in detail herein and with respect to a present preferred form which it may assume, it i not to be limited to such forms and details since many changes and modifications may be made in the invention without departing from the spirit and scope of the invention in its broadest aspects. Hence it is desired to cover any and all forms and modifications of the invention which may come within the language or scope of any one or more F of the appended claims.

What we claim as our invention, is: i

1. The method of dyeing textile fabrics which comprises applying a paste, containing a dye which in combination with a, swelling agent is capable of directly dyeing cellulose acetate, a solvent for said dye, a swelling agent for cellulose acetate, and a thickening agent, to a single surface of a fabric which surface comprises cellulose acetate ends and ends of a different material which is not capable of being directly dyed by said dye in combination with said swelling agent, said application of the paste being mad with a sufi'iciently thick paste and. with sufiiciently low pressure to restrict the penetration of said paste into said fabric, said application of the paste contacting both cellulose acetate ends and said other ends, and removing the paste from said surface while preventing dye from said paste from dyeing cellulose acetate ends on the surface of said fabric opposite said first-named surface.

2. The method of dyeing textile fabrics which comprises applying in a continuous manner a paste, containing a dye which in combination with a swelling agent is capable of directly dyeing cellulose acetate a solvent for said dye, a swelling agent for cellulose acetate, and a thickening agent, to a single surface of a fabric which surface comprises cellulose acetate ends and ends of a different material which is not capable of being directly dyed by said dye in combination with said swelling agent, said application of the paste being made with a sufficiently thick paste and with sufficiently low pressure to restrict the penetration of said paste into said fabric, said application of the paste contacting both cellulose acetate ends and said other ends, and removing the paste from said surface while preventing dye from said paste from dyeing cellulose acetate ends on the surface of said fabric opposite said first-named surface.

3. The method of dyeing textile fabrics which comprises applying a, paste, containing a dye which in combination with 'a swelling agent is capable of directly dyeing cellulose acetate, a solvent for said dye, a swelling agent for cellulose acetate, and a thickening agent, to a single surface of a fabric which surface comprises cellulose acetate ends and ends of cellulosic material which is not capable of being directly dyed by said dye in combination with said swelling agent, said application of the paste being made with a sufficiently thick paste and with sufiiciently loW pressure to restrict the penetration of said paste into said fabric, said application of th paste contacting both cellulose acetate ends and said other ends, and removing the paste from said surface while preventing dye from said paste from dyeing cellulose acetate ends on the surface of said fabric opposite said first-named surface.

4. The method of dyeing textile fabrics which comprises applying in a continuous manner a paste, containing a dy which in combination with a swelling agent is capable of directly dyeing cellulose acetate, a solvent for said dye, a swelling agent for cellulose acetate, and a thickening agent, to a single surface of a fabric which surface comprises cellulose acetate ends and ends of cellulosic material which is not capable of being directly dyed by said dye in combination with said swelling agent, said application of the paste being made with a, sufficiently thick paste and with sufficiently low pressure to restrict the penetration of said paste into said fabric, said application of the paste contacting both cellulose acetate ends and said other ends, and removing the paste from said surface while preventing dye from said paste from dyeing cellulose acetate ends on the surface of said fabric opposite said first-named surface.

5. The method of claim 1, in which the swelling agent is a metal thiocyanate.

6. The method of claim 1, in which the thickening agent is a cellulos ether.

7. The method of claim 1, in which the solvent for the dye is a lower aliphatic alcohol.

8. The method of claim 1, in which the dye paste is applied to the fabric at a temperature greater than 60 0., and the solvent for the dye is ethyl alcohol, whereby the solvent for the dye swells th cellulose acetate.

BERTRAM J. GOLDSMITH. WALTER H. HINDLE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 617,772 Rettig Jan. 17, 1899 1,599,910 Mijer Sept. 14, 1926 1,688,553 Olpin Oct. 23, 1928 2,133,470 Olpin Oct. 18, 1938 2,248,048 Allan July 8, 1941 2,428,836 Croft Oct. 14, 1947 FOREIGN PATENTS Number Country Date 570,880 Great Britain July 26, 1945 OTHER REFERENCES Knecht & Fothergill, Textile Printing, published in London by Charles Griffin, 3rd edition, 1936, pages 138, 139. (Available in Div. 43 of Patent Oflice.) 

1. THE METHOD OF DYEING TEXTILE FABRICS WHICH COMPRISES APPLYING A PASTE, CONTAINING A DYE WHICH IN COMBINATION WITH A SWELLING AGENT IS CAPABLE OF DIRECTLY DYEING CELLULOSE ACETATE, A SOLVENT FOR SAID DYE, A SWELLING AGENT FOR CELLULOSE ACETATE, AND A THICKENING AGENT, TO A SINGLE SURFACE OF A FABRIC WHICH SURFACE COMPRISES CELLULOSE ACETATE ENDS AND ENDS OF A DIFFERENT MATERIAL WHICH IS NOT CAPABLE OF BEING DIRECTLY DYED BY SAID DYE IN COMBINATION WITH SAID SWELLING AGENT, SAID APPLICATION OF THE PASTE BEING MADE WITH A SUFFICIENTLY THICK PASTE AND WITH SUFFICIENTLY LOW PRESSURE TO RESTRICT THE PENETRATION OF SAID PASTE INTO SAID FABRIC, SAID APPLICATION OF THE PASTE CONTACTING BOTH CELLULOSE ACETATE ENDS AND SAID OTHER ENDS, AND REMOVING THE PASTE FROM SAID SURFACE WHILE PREVENTING DYE FROM SAID PASTE FROM DYEING CELLULOSE ACETATE ENDS ON THE SURFACE OF SAID FABRIC OPPOSITE SAID FIRST-NAMED SURFACE. 